Electric switch



Oct. 14, 1947.v M. F. KoENlG ErAL 2,428,848

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Patented ocr. 14, l1947 UNITED STATES PATENT OFFICE ELECTRIC SWITCH Martin F. Koenig and Alvin W. Krieger, Milwaukee, Wis., assignors to Cutler-Hammer, Inc., Milwaukee, Wis., a corporation of Delawarey Application March 21, 1945, Serial No. 583,974

` 8 Claims.

This invention relates to improvements in electric switches, and more particularly to a novel form of combined switch and electromagnetic indicator.

A primary object of the invention is to provide a novel form and arrangement of the switch parts and a novel form and arrangement of the electromagnetic indicating means to facilitate positioning thereof within a single housing.

Another object is to provide a novel' form of housing adapted to support the switch mechanism at one end `thereof and the indicating means at the other end thereof, while at the same time enabling location of the manually operable lever in recessed insulating base into which most ofthe switch and indicator parts may be readily inserted and thereafter retained by merely attaching the cover member.

Another object is to provide means integralwith the cover member to enable attachment thereof to the base and to afford an armored covering for the main sides of the latter.

Another object is to provide a switch of the aforementioned character of relatively small size with respect to its current controlling capacity.

Other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate certain embodiments of the invention, which will now be described; it being understood that the embodifled form mediate olif position, a momentary on posiments illustrated are susceptible of modification switch parts and indicator parts being shown in elevation, and the contactor being of a. type affording an intermediate off position. and a 2 momentary on" position when moved in each direction.

Fig. 3 is a bottom plan view 0f the device shown in Figs. 1 and 2, showing the bus connections between the coil leads and certain of the wiring terminals of the switch.

Fig. 4 is a horizontal sectional view, on the broken line I--I of Fig. 2;

Fig. 5 is a vertical section, on the line 5-5 of Fig. 2.

Fig. 6 is a view partly in side elevation, and partly in vertical section, of a device like that of Figs. l to 5, `but with a. modiof contactor affording an intertion when moved in one direction, and a nonmomentary on position when moved in the opposite direction.

Fig. 'l is a view similar to Fig. 6, but with a still further modified form-of contactar to provide a non-momentary on" and o switch; the lefthand contact acting as a dummy to afford this characteristic; and the coil of the indicator having-separate terminal members associated therewith to provide for a different type of circuit connection, and o Fig. 8 is a bottom plan view of the device shown in Fig. 7. i

Referring first to the device shown in Figs. 1 to 5, the numeral I0 designates a molded insulating base of substantially rectangular contour; said base being of relatively small width and of relatively greater length and depth. Base 0 is provided at the left-hand side thereof (Fig. 2) with a substantially rectangular recess II, the bottom wall of which. is provided with three equally spaced' circular openings or passages I2, I3 and I4 to accommodate the Shanks of a cor- The rivets I5 and Il are composed of silver, or a composition or alloy including silver; where- `by the heads I5 and f1 thereof are respectively adapted to lact as stationary contacts of the switch. Saidrivets I5 and II may, of course, be of identical form and the aforementioned heads I5 and I1 thereof have washers I 8,. I8 underlying the same as illustrated. 'I'he shank ends of said rivets penetrate openings provided in a pair of like wiring terminal members I9, I9, and said ends are upset over said terminal members, as shown at I5b and I1h in Fig. 2.

Said terminal members have portions bent downwardly at a right angle to the lower surface of Ibase III and are tapped to accommodate the Shanks of binding screws 20 of well known form.

The head of rivet i6 overlies the intermediate or connecting portion of a. Contactor supporting bracket 2l which is positioned within a correspondingly shaped recess Illa in said bottom wall to positively prevent rotation of said bracket; both rivet i8 and bracket 2l being preferably composed oi brass, with a plating of silver. The shank of rivet i6 is adapted to penetrate an opening in a third terminal member I9, and is upset over the latter as shown at ISB.

As shown in Figs. 2 and 3, the lower surface IGb of base EU. is provided with depressions to accommodate the correspondingly shaped portions of the terminal members I9, to positively prevent relative rotation of the latter; the terminal member i9 associated with rivet IB also having a binding screw 20 associated therewith. The vertical upstanding arms 21a and 2|b of member 2i have upwardly opening rectangular notches 2|c and 2|d formed therein to accommodate the lateral projections 22 and 22b formed upon the Contactor 22.

Contactor 22 is preferably stamped to the form illustrated in Figs. 2 and 5 from a suitable blank punched from a bimetallic strip, the arrangement being such that the Contactor has a lower layerof lamination 22c of silver and an upper layer 22d of the base metal such as copper. The intermediate portion of Contactor 22 is bent to approximately V-shape, the inclined cam surfaces 22e and 22I of which meet or merge in a concave portion 228 below the plane of the aforementioned lugs 22 and 22h; the manner in which the latter are upwardly oset being best illustrated in Fig. 5. Each end portion of Contactor 22 is bent as shown to extend upwardly at a predetermined angle from the cam surfaces 22e and 221, then downwardly at a predetermined angle, and then endwise` at'v -ver tip portions 22h and 221, whereby said tips are adapted to engage or abut fiatwise against flat heads 15a and il of the silver rivets aforementioned.

Contactor 22 is adapted to be continuously engaged by the rounded or hemispherical lower end 23a of an insulating plunger 23 of circular form in transverse cross section. Plunger 23 is provided with a reduced upper end portion 23 adapted to t within the lower end of a coiled compression spring 24; the lower end coil of said spring seating against the shoulder formed by portion 23h. The upper end of spring 24 seats against the upper end of a cylindrical recess 251 formed in a metal lever 25; the arrangement being such that when the parts are as-y scmbled spring 24 will be placed under a predetermined degree of compression, whereby the same tends to eject plunger 23 outwardly from said'recess. As shown in Figs. 2 and 5, plunger 23 normally projects a substantial distance beyond member 25.

Member 25 is provided intermediate its length with a partially spherical enlargement 25h which merges into the upper and lower portions of said member. Enlargement 25b ts a ball within the upper portion 26 of a socket; said portion 2Bl Abeing formed integrally with and bent upwardly from the connecting portion 26h of a substantially U-shaped bracket member whose upstanding parallel sides or arms are designated by numerals 26 and 2lid (Figs. 2 and 5). The lower portion 2la of the socket is formed integrally with and bent downwardly from a metal plate 21 which is preferably coextensive with the area of the bracket portion 26", said plate 21 being spot-welded or otherwise rigidly attached at at least two diagonally opposed corners thereof with said portion 2Gb to retain said socket portions in xed relationship to each other. As best illustrated by comparison of Fig. 5 with Fig. 2, the openings provided in the respective socket portions 26 and 2l are of somewhat elliptical contour, whereby the same are'adapted to afforda clearance for the upper and lower end portions of member 25 during oscillatory movement of the latter while acting to limit the same to oscillatory movement in a single plane.

As best illustrated in Figs. 4 and 5, the opposite side walls of recess Il are respectively provided with rectangular indentations or grooves I IEl and Ilb which open to the upper surface of base il), said indentation's being adapted to accommodate in a flush relationship the aforementioned bracket arms ZEG and 26d. As shown in Fig. 5, the horizontal shoulders Ilc and Hd formed by said indentations HL and IIb, respectively, are adapted to serve as seats for the opposite side portions of plate 2l, so that when the aforementioned bracket'is inserted into recess ll the upper ends of the arms 26c and 26d will be positioned flush with the upper surface of base 10.

As shown, lever 25 is provided with an upwardly opening kerf or cut 25, which is adapted to loosely receive one perforated end of a metal link 28; said lever having adjacent its upper end a circular passage or opening 25d extending through said kerf at a right-angle to the plane of the latter. A headed pin 29 has its shank 'penetrating said last mentioned opening and the perforated end of link 28 to provide a pivotal connection between said parts, the shank end being upset as shown to secure said parts in assembled position. The other perforated end of link 28 ts loosely into a. kerf 30a (Figs. 4 and 5) in the lower end of a manually operable lever 30; said lower end having therein a circular passage or opening :lilb extending through said kerf at a right angle to the plane of the latter. A headed pin'3i has its shank penetrating said last mentioned opening and the perforated end of link 28 to provide a pivotal connection between said parts, the shank end being upset as shown to secure said parts in assembled position.

As shown at 30c in Fig, 2, the lower end of lever 30 is partially rounded to insure proper clearance between the same andlever 25 during pivotal movement of the respective parts. Lever 30 is provided intermediate its length with a circular opening (not shown) to accommodate with a drive fit the intermediate enlarged portion of a pin 32 (Figs. 2 and 5); the oppositely extending ends of which pin are adapted to bear within open pivotal bearings formed in the upper edges of the side walls 26c and 26d of recess 26; one of said bearings being shown in dotted lines at 26e in Fig. 2. The upwardly projecting portion of lever 30 is preferably shaped as illustrated to facilitate manipulation thereof by the lthumb and/or the index finger of an operators hand.

Base I 0 is provided at its right-hand end (Fig. 2) with a recess 33 of substantially square form in transverse cross section, said recess' 33 being separated from recess il by a vertical wall 34 which is provided at its upper end with a relativeLv wide rectangular notch 3l* to provide clearance for lever 30 upon oscillation of the latter. Recess 33 is adapted to accommodate a substanl of insulation or the like.

33. One upstanding arm 35b of said bracket is provided with a forked extension whose portions 38, 38 (Figs. 2 and 4) are located flush with the upper surface of base I8. 'I'he other upstanding arm 384'01' said bracket is likewise provided with a forked extension, the portions 35, 38 of which end short of the upper surface of base I8.

A wire of extremely small gauge is wound in the form of a coil 38 around a bobbin or spool 31 formed of a suitable insulating material, such as Bakelite The passage 31 through said spool is adapted to accommodate a pin or supporting stud 38, the reduced lower end of which penetrates an opening of corresponding size in the connecting portion 35l and is upset over the lower surface of the latter. as shown at 38 in Fig. 2. The upper end 38b of said pin is preferably of coneshape to accommodate the lower end lof a coiled compression spring 38, whose upper end engages the end wall of a downwardly opening recess 48 formed in a metal plunger 48.

Plunger 48 is provided adjacent its upper end with a reduced or neck portion 48b to accommodate the forked end 4I of a flat, punched sheet metal member 4I. Member 4I is provided with a perforation to accommodate the reduced or shank end of a metal member 42, said shank end being upset over the lower surface of member 4I as indicated at 42L to secure said parts to each other. 'Member 42 is provided with an integral annular flange portion 42h which is adapted to engage the lower surface of a metal bushing 44 attached to the cover member 43 of the device, said bushing having an integral portion 44' there,- of upset over the upper surface of cover member 43 for this purpose. Bushing 44 thus acts as a guide for member 42; the hollow upper end of the latter having cemented therein or otherwise rigidly attached thereto a cylindrical member 42c The flat upper end of member 42 is. preferably of a dark color such as black; whereas the peripheral portion thereof projecting beyond member 42 is preferably provided with a coating of luminous paint.

Spool 31 is provided at its upper end withan annular extension 31, and a flat punched sheet metal plate 45 of square form has an opening to accommodate said extension. The opposite arms "of bracket 35 are provided with integral lugs 35f and 35 which are bent inwardly over plate 45 to rigidly secure the latter and the coil assembly within said bracket.

Recess 33 is provided in its bottom wall with a pair of openings 46 and 41 to accommodate the opposite ends of the wire of which the coil 38 is formed (see Fig. 3)'. Said wire ends have terminal extensions of different lengths attached thereto, as indicated by numerals 38 and 36h, the portions 36 and 36'i of said extensions being adapted to flt within grooves 48 and 48 in the lower surface of base I8, to provide for electrical connection of one end of the coil wire to the lefthand terminal member I8 (Fig. 3) and for connection of the other end of the coil wire to the intermediate terminal member I8. As shown in Fig. 8, however, said extensions 36 and 36b may be made of relatively shorter, substantially equal, lengths to provide for attachment thereof to a pair of wiring terminal members individual to the coil; as hereinafter more fully described.

As best illustrated in Fig. 3. the lower surfaceof base I3 is provided with rectangularl recessesmembers as shown at I8, I-8 in Fig. 8; saldrecesses 68 and 8l respectively having countersunk portions providing relatively thin integral diaphragme which may be broached or otherwise removed to accommodate the shanks of securing rivets `(not shown). In each case, the bared ends of the coil extension wires are preferably soldered, brazed or otherwise rigidly and permanently attached to the horizontal portions of the respective terminal members I8, thus leaving the respective binding screws 28 free for attachment of the circuit wires. n

The aforementioned cover member 43 is provided with integral, downwardly extending arms 43 and 43b which nt into grooves .of corresponding size formed in the respective main sides of base I8 (as best illustrated in Fig. 4). spective arms 43 and 43h of cover member 43 are likewise provided with integral lugs 43, 43 and 43e 43f which are bent inwardly over the downwardly facing walls of notches or counter'sinks in the lower surface of base I8 to rigidly secure said parts in Iassembled relation.

As best illustrated in Figs. 2 and 5, the cover member 43 overlies the opposite ends of pivot pin 32 to retain the same within the aforementioned bearings in the side walls of base I8, said cover y, member 43 having a rectangular opening 43l (Fig. 2) formed therein to provide for assembly thereof over the projecting end of lever 38`and to provide oscillatory clearance for the latter.

Cover member 43 has attached thereto at opposite ends thereof a pair of interiorly threaded members 52, 52 (see Fig. 4) which act as lock nuts in a well known manner, to accommodate the shanks of bolts or screws (not shown) whereby the complete device may be attached to the inner surfaceof a suitable panel or similar support.

As best illustrated in Figs. 1, 2, 6 and?, the aforedescribed mechanical arrangement of the parts is such as to provide for proper positioning of lever 38 in a central or symmetrical location relatively to the cover member 43. Also as shown, the coil 36 when deenergized permits the indicating portion 42c of member 42 to project outwardly beyond bushing 42 under the bias of spring 38. On the other hand, upon energization of coil' 36, plunger 48 is drawn inwardly against the bias of spring 38, at the same time retracting member 42 and the indicating portion 42 of the latter.

With the terminal wires 36 and 36 of the coil 36 connected as shown in Fig. 3, it may be assumed that the righthand terminal member I8 has attached thereto by means of its binding screw 28 a wire leading from a suitable source of current supply. The intermediate terminal member (which has one terminal wire 36 of the coil 36 attached thereto) may be connected by its binding screw 28 to one terminal of the operating winding of an electromagnetic switch or contactor (not shown), the other terminal of which winding is connected to ground. Similarly the The re- 7 through the contactor 22 and the intermediate terminal member I9 to and through the operating coil (not shown) of an electromagnetically operable switch, and thence to ground. At the same time a circuit will extend from the right-hand terminal I9 through contactor 22 and the intermediate terminal I9, thence by the terminal wire 36d of coil 36 through the latter, and by the other terminal wire 36 of said coil to the left-hand terminal member I9, thence to ground; thus providing for energzation of coil 36 and retraction of the indicating element M associated therewith In practice the circuit arrangement (not shown) is preferably such that the energizing circuit of the aforementioned electromagnetically operable switch is maintained independently of the contactor 22, after initial completion of such energizing circuit, so that upon manual release of lever 30 the switch parts will again assume the respective positions thereof illustrated in Fig. 2, but the coil 36 will remain energized and the indicat- `ing element 44 will remain in its retracted position.

Under the conditions last mentioned, upon counterclockwise movement of lever 30 the lever 25 will be moved in a clockwise direction to effect engagement of contactor tip 22h with the lefthand stationary contact tip l; the circuit arrangement preferably being such that both the operating coil of said electromagnetically operable switch and the coil 36 aforementioned will be short-circuited to eiect deenergization thereof.

A circuit of the character aforedescribed is disclosed in the copending application of A. P. Charbonneau, F. J. Russell and E. W. Seeger, Serial No. 444,304, filed May 25, 1942, for Electric circuit controller.

In the modified form of our invention illustrated in Fig. 6, all of the parts except the contactor 54 may be identical with the corresponding parts aforedescribed. The contactor 5l differs from the contactor 22 in that the left-hand end 54a of the former is adapted upon clockwise movement of lever 25 (as an incident to counterclockwise movement of lever 30) to provide for nonmomentary engagement of contactor tip 54b with stationary contact tip l5; lever 25 being also adapted for manual movement to provide momentary engagement of contactor tip 54d with stationary contact tip I'l; and lever 25 being further adapted for manual movement' to and automatic retention in its intermediate off position illustrated.

Upon movement of lever 25 in a counterclockwise direction from the position thereof illustrated, the right-hand portion 54C of contactor 54 cooperates with the spring pressed plunger 23 to provide for momentary engagement of contactor tip 54d with the stationary contact tip Il; disengagement of said tips being effected automatically upon manual release of lever 30, with return of contactor 5 4 to the intermediate olf position thereof illustrated. The three wiring terminal members i9 and their associated binding screws 20 may be the same as those employed in the device of Figs. 1 to 5; the operating coil 36 preferably having its terminal wires (not shown) respectively connected to the left-hand and center terminal members I9, I9, as shown in Fig. 3.

In the device of Figs. '7 and 8 the contactor 55 is shaped to provide for non-momentary engagement of contactor tip 525i with stationary contact tip |18 upon counterclockwise movement of lever 25 from its left-hand position, so that the lower end of plunger 23 rides over the intermediate or central hump 55e of said contactor. Upon clockwise movement of lever 25 from the righthand extreme position thereof illustrated to its left-hand extreme position, so that plunger 23 rides over hump 55e in the reverse direction, contactor tip 55f will be non-momentarily engaged with the stationary contact tip I5. In this instance, however, there is no terminal member connected with the shank of rivet I5, so that the tip l5* merely acts as a dummy" to provide an oi position for the switch. In Figs. 7 and 8, the wire ends 36 and 35h of coil 36 are relatively shorter than those aforedescribed, said ends (see Fig. 8) being soldered, brazed, or otherwise rigidly connected to the horizontal portions of a pair of auxiliary terminal members I9, I9 whose binding screws 20, 20 provide for attachment of suitable circuit wires. The switch itself in Figs. '7 and 8 is provided only with a right-hand terminal member i9 and a so-called intermediate terminal I8, each being provided with a binding screw 2l; the end wires of the coil 36 being un-connected with said last mentioned terminals in the device of Figs. '7 and 8.- In this arrangement it may be assumed that contactor 55 will provide for completion or interruption of the energizing circuit of an electromagnetically operable switch, and that the latter will in turn control the energizing circuit of coil 36.

As aforeindicated, the combination device herein disclosed was designed to meet the space limitations of similar electrical devices to be attached to the control panel of an airplane or the like. For example, the present combination device may be applied to a panel prepared to accommodate a circuit breaker of the character disclosed in Patent No 2,342,945, granted February 29, 1944, to A, W. Krieger.

As best illustrated in Fig. 1, cover member ll is provided with two pairs of parallel ribs or bosses 431 `and 43h to insure proper seating thereof against the inner surface of a supporting panel, and to avoid interference with such seating by the upset or riveted portions upon the upper surface of said cover member.

We claim:

l. In combination, a. molded insulating base having a relatively large recess and a relatively small recess formed therein in side by side relationship and opening to one end of said base, a manually operable switch mechanism positioned within said large recess and an electromagnetically operable indicating device positioned within said small recess, a cover member secured to said base and overlying both of said recesses, said cover member acting to retain all parts of said indicating device and the movable parts of said switch mechanism in assembled relationship to said base, said cover member having therein an opening to afford clearance for a reciprocating part of said indicating device and a second opening to afford clearance for an oscillatable operating part of said switch, and means including a plurality of wiring terminal members exposed at the lower surface of said base to provide for connection of said switch and said indicating device to a suitable source of current supply and to provide for control of said indicating device by said switch.

2. In combination, a molded insulating base having a relatively large recess and a relatively small recess formed therein in side by side relationship and opening to one end of said base, a manually operable switch mechanism positioned within said large recess and an electromagnetioauy operable indicating device positioned within said small recess, a cover` member secured to said base and .overlying both of said recesses, said cover member acting to retain all parts of said having alink pivotally connected thereto and to another oscillatable part of the switch.

5. In an electric switch, in combination, a molded insulating base having a recess formed indicating device and the movable parts of said therein andopening to the upper end thereof, a

switch mechanism in assembled relationship to said base, said cover member having therein an opening to afford clearance for a reciprocating part of said indicating device and a second opening to afford clearance for an oscillatable operating part of said switch, meansincluding a plu- Vrality of wiring terminal members exposed at the lower surface of said base to provide for con-A nection .of said switch and said indicating device to a suitable source of current supply and to provide for control of said indicating device by said f switch, and certain of said wiring terminal members being common to said switch and said indicating device.

ypair of stationary contacts secured to the bottomvwall of said recess, a fulcrum member also secured to said wall between said contacts, a punched and stamped laminated sheet metal contactor oscillatably supported by said fulcrum member, said contactor having a pair of oppositely extending arms bent to provide a pair of oppositely inclined cam surfaces meeting below the point of support thereof, the lower lamination of said contactor comprising silver and said arms being shaped to provide for engagement of portions of said lamination with the stationary co'ntacts selectively, an actuating lever pivotally supported at an intermediate point in the depth 3. In combination, a molded insulating base of said recess, said lever having an associated having a relatively large recess and arelatively small recess formed therein in side by side relationship and opening to one end of said base, a manually operable switch mechanism positioned cally operable indicating device positioned within said small recess, a cover member secured to said base and overlying both of said recesses, said cover member acting to retain all parts of said.

spring-biased member continuously engaged with said contactor, whereby the latter is normally biased to its intermediate off position, a second lever pivotally supported by the side walls of said within said large recess and an electromagne'ti-` 25 recess at the upper end of the latter, said levers being normally positioned in vertical planes offset from each other, said first lever having a kerf in its upper end and said second lever having a e kerf in its lower end, a, vlink having its ends posiindicating device and the movable parts of said 30, tioned within the respective kerfs and pivotally switch mechanism in assembled relationship to said base, said cover member having therein an opening to afford clearance for a reciprocating part of said indicating device and a second opening to afford clearance for an oscillatable operating part of said switch, means including a plurality of wiring terminal members exposed at the lower surface of said base to provide for connection of said switch and said indicating device to a suitable source of current supply and to provide for control of said indiacting device by isaid switch, said cover member having integral paral-T connected with the respective levers, and a cover formed therein in side by side relationship and opening to one end of said base, a manually operable switch mechanism positioned within one of said recesses and an electromagneticallyoperable indicating device positioned within an- 40 other of said recesses, a cover member overlying both of said recesses, said cover member having \vtl1erein an opening to afford clearance for a part of said indicating device and a second opening to afford clearance for an operating part of said switch, means including a plurality of wiring terminal members to provide for connection of said switch and said indicating device to a suitable source of current supply and to provide for control of said indicating device by said switch,

and certain of said wiring terminal members being common to said switch and said indicating device.

'7. In combination, an insulating base having recesses formed therein and opening to one en'd base and overlying both of said recesses, said thereof, a switch mechanism positioned within cover member acting to retain all parts of said indicating device and the movable parts of said switch mechanism in assembled relationship to said base, said cover member having therein an one of said recesses, said switch including a pivotally supported lever, the support for said lever comprising a bracket positioned within said first mentioned recess above the bottom wall of the opening to afford clearance for a, reciprocating 00 latter, said bracket and lever being formed to part of said indicating device and a second opening part of said switch, means including a plurality of wiring terminal members exposed at the lower surface of said base to provide for connection of said switch and said indicating device to a suitable source or current supply and to provide for` control of said indicating device by said switch, said cover member having integral parallel arms overlying the opposite sides of said base, said arms each having a plurality of in- /tegral lugs bendable inwardly over said base adjacent the lower end of the latter, said oscillatable operating part of said switch fbeing positioned provide a ball and socket connection therebetween, a second lever having a pivotal connection with the side walls of said first mentioned recess at the upper end of the latter and in a plane off- 05 set from the plane of pivotal support of said first lever, a link 'having a pivotal connection with the upper end of said first lever and the lower end of said second lever, said second lever having a manually engageable portion projecting upwardly beyond said base, a substantially U-shaped metal bracket positioned within the other recess and having at least one arm thereof extending upwardly into substantially flush relationship to the upper end of said base, a metal core member centrally of said cover member, and the same upstanding from the connecting portion of said last mentioned bracket and rigidly attached thereto, an insulating spool slidable onto said core and seated upon said connecting portion, a wire coil wound upon said spool, a plurality of lugs formed integrally with said last mentioned bracket and bent inwardly over said spool to hold the same in assembled position, a metal plunger slidable within said spool and having a downwardly opening recess, a spring interposed between the end wall of said plunger recess and said core to bias said plunger toward the upper end of said base, an indicating member having a loose interlocking connection with said plunger at the upper end of the latter, a cover member secured to said base and having an opening therein to guide said indicating member and limit the degree of outward movement thereof, said cover member also acting to retain said brackets and the pivotI of said second lever in assembled relationship to said base, and associated means to provide for energization and deenergization of said coil in accordance with the operation of said switch. v

8. In combination, an insulating base having a recess formed therein and opening to the upper end thereof, a switch mechanism within said recess. said mechanism including stationary contacts and a contactorpivotally movable into and out of engagement with said contacts selectively, an actuating lever for said contactor, said lever being pivotally supported at an intermediate` point in the depth of said recess,.a second lever pivotally supported by the side walls of said recess at the upper end of the latter, said levers being normally positioned in vertical planes odset 35 1,141,119

' from each other, a link plvotaliy connectedwith the respective levers, a cover member overlying said recess to retain both of said levers in assembled relationship to said base, the supporting means for said first mentioned lever comprising a substantially U-shaped metal bracket adapted to seat within said recess in a substantially flush relationship to the upper end of said base, said rst lever having a partially spherical enlargement intermediate its ends, the connecting portion of said bracket having a downwardly facing socket adapted to accommodate the upper portion of said enlargement, a punched and stamped sheet metal plate rigidly secured to the lower surface of said connecting portion, said plate having an upwardly facing socket adapted to accommodate the other portion of said enlargement, and said connecting portion and said plate having slots formed therein for cooperation with portions of said lever above and below said enlargement to limit said first lever to oscillatory movement in substantially a single plane.

The following references are of record in the file of this patentz" UNITED STATES PATENTS Number Name Date 2,027,538 Krieger Jan. 14, 1936 V1,666,238 Mener Apr. 17, 1928 Kaisling Jan. 1, 1915 

